--- orig.isl-0.14/configure	2014-10-26 08:36:32.000000000 +0100
+++ isl-0.14/configure	2016-10-10 18:16:01.430224500 +0200
@@ -8134,7 +8134,7 @@
      lt_sysroot=`$CC --print-sysroot 2>/dev/null`
    fi
    ;; #(
- /*)
+ /*|[A-Z]:\\*|[A-Z]:/*)
    lt_sysroot=`echo "$with_sysroot" | sed -e "$sed_quote_subst"`
    ;; #(
  no|'')